Graduated air-feed relief for rock drills



May 18 1926. 1,584,817

F. M. SLATER GRADUATED AIR FEED RELIEF FOR ROCH DRILLS Filed OCT., 5, 1922 vwamboz 351g his l il.

Fatented ltflay l, ltlt tattili-TE@ llllapllld ,Staan lFRED M. SLATER, OF EASTON, PENNSYLVANIA, ASSIGNOR, TO hl'GERSGLL-RANI) COM- ?ANY, OF JERSEY CITY, NEW JERSEY, A CRPOVRATION OF NEVI JERSEY.

GRADUATED .AIR-FEED RELIEF FOR RGCK DRLLS.

Application lcd October 5, 1922. Serial No. 592,488.

@ne object ofthe invention is to enable vthe air feeding element to. be regulated as desired by a pressure controlling device, which may be manipulated by hand and is sufliciently sensitive and accurate to cause the feeding element to respond substantially in accordance with the degree of movement of the regulating device or force applied to movethe device.

Another object of the invention is to secure a pressure controlling device by means of which the feeding element may be started and continued in operation or checked and held substantially stationary in a condition of equilibrium Without dropping back or maybe otherwise manipulated with certainty and precision, both on starting a hole and after drilling has commenced.

The invention is shown in the accon'ipanying drawings, in Which- Figure l is a -side elevation. partly in longitudinal section of a stope drill embodying the invention,

Figure 2 an enlarged det-ail transverse sectional View taken through the regulating valve on the line 2 2 of Figurel looking in the direction of the arrows,V i

Figure 3 is an enlarged detail longitudinal sectional vievv partly broken away through the regulating valve on the line 3-3 of Figure 2 looking in the direction of the arrows, and v Y Figure l isa side view similar to Figure 8 With the valve in a different position.

Referring to the drawings, which illustrate the invention applied to a stope drill, it is to be understood that only so much of the operative parts of the stope drill are shown as Will serve to explain the invention and its operation. y

The machine comprises a cylinder A, adapted to contain a fluid actuated hammer piston, and the drill steel B extends Within the front head C to receive the blovvsy of iin-k pact of the piston.l 'The fro-nt head C is connected to the .cylinder bymeans of the usual side bolts D and the cylinder back head E, the head block F, and the feed cylinder head G of the lfeed cylinder H, are connected together by the bolts J. A feed' piston K having a piston rod L moves in the feed cylinder H and the. piston rod is provided with al rockenga'ging point O. The motive fluid for operating the machine is supplied at the throttle l), manipulated by the handle Q, mounted on the back head E. The ports and'passages forsupplying motivelluid to the cylinder A are not indicated, as they form no part of the present invention. The passage lt indicated in dotted lines in Figure l leads to the head block F and from thence to the air feed cylinder l-l for supplying pressure fluid to the feeding element. The supply of pressure fluid to the feeding element and the escape of pressure fluid from said element are controlled byv the hand manipulated valve S mounted in a valve chest T contained in the head block F.

The back head E of the machine is provided With the usual handle U commonly called the rotation handle, and the valve S is manipulated by means of the hand lever V pivoted at W on the head block F and provided With a lever arm X bearing on the end Y of the valve S projecting from the valve chest. A spring Z normally maintains the hand lever V in retracted position, but as this lever is mounted ladjacent the rotation handle U, both levers and V are grasped by the operator at the same time and by pressing upon the lever V the controlling valve S Will be manipulated to a greater or less extent according to the degree of pressureapplied to the lever V and in accordance with the movement of said lever.

The valve S, as shown, is hollow and contains a spring a., bearing at one end against a plug b containing an atmospheric Avent vc communicating With the interior of the valve.

'lhe valve chest T formed in the head .block F is in this instance provided with the series of ports (Z forming graduated supply ports leading to the air feed cylinder H and controlled by the valve S. The valve is `provided With the groove c cooperating with the supply ports d.

ln this instance, the valve chest is with the groove f cooperating with the escape ports g in the valve body S forming graduated escape ports.

The valve and its ports and passages are so constructed and arranged, that the supply to the air feed cylinder H through the supply ports l and thence around the groove e and thence through the port lt to the air feed is never entirely cut otf, so that motive fluid is continually being supplied to the air feed cylinder regardless Aof the position of formed i the valve. The valve is shown in normal position in Figure 3 with full supply passingr to the air feed cylinder, and the escape of fluid through the port is entirely cut oil. By pressing upon the lever handle V, the valve S is moved longitudinally in the chest against the spring a and as the valve is moved, the supply port c is continually re-y duced, but the amount of pressure fluid permitted to escape through the escape ports g is continually increased until the valve reaches the position shown in Figure il at Ithe limit of its inward' travel. hlotive fluid is still being supplied in the n'iinimuin amount to the air feed cylinder, while the maximum amount ol' fluid is escaping from the cylinder through :the escape lports g andthence through the valve to the atmosphere at'the 'port c. it intermediate positions of the valve,l iluid is being supplied to the cylinder at the same time that fluid is escaping therefrom. Byineans ot this arrangement and because ot the fact that the supply to the cylinder is never entirely cut oil', althoughv the escape or bleeder ports may be fully open, l am enabled to Iobtain extremely sensitive regulation and control of the air feeding element. I have found that in accordance with my construction, I am enabled to start and stop the feeding o1 the machine at will and hold the machine substantially stationary at any desired point without permitting the air feed cylinder to drop back on the piston ll. rlhis is an important feature, because accidents may result itthe air feed permits the machine tov sink when not desired, while on the other hand I am enabled to instantly check the feeding by pressing to the refpiircd extent upon the controlling handle V of the regulating device. My controlling device is extremely sensitive because the air feed control is graduated through a sufficient range to obtain any desired-result in a positive manner.

I claim:

l. A controlling device for the air teef ing element of a fluid actuated rock drill comprising a valve chest, a plurality of spaced supply ports and relieiI port means in said valve chest, a reciprocatory valve in the valve chest to control the supply ports, said valve being` hollow and provided with apertures extending through'the vside o'li the valve to communicate with the said relief port means, manually operable means tov move said valve in one direction to close the supply ports and open the rcliet port means gradually wlierebyair in the air feed element may be gradually released, and means in the valve for automatically moving the valve in the opposite direction.

2. A controlling device for the air feeding clement orn a lluid actuated roch drill comarising a valve chest, a plurality oit spaced supply ports and relief port means in said valve chest, a rcciprocatory valve in the valve chest to control the supply ports and relief port means, said valve being hollow and provided with apertures extending through the side ot the valve to communicate with the said relief port means, a spring normally tending to hold the valve in position openthe supply ports, and manually opcrable means to move said valve in a direction to close the supply ports and open the said relieiI port means gradually whereby air in the air feed element may be gradually rcleased.

3. A controlling device 'for the air feeding element ot a lluid actuated rocl; drill comprising a valve c 5t provided with a pl urality of spaced supply ports and rclic't port means, a reiprocating valve in the chest to control the supply ports and the said rclief port means and having an cud projecti ing` from the valve chest, said valve beingr hollow and provided with apertures extending through the side of the valve to coinmunicate with the said relief port mean-1, a lever mounted pivotally on the 'valve chest to move said valve in one direction to close the supply ports and open the i'clielf port means gradually whereby air in the air .l'ecd element may be gradually released. and a spring in said valve ior automatically moving the valve in the opposite direction l'or closing the reliei port means and opening the supply ports.

il controlling device for the air feeding element of a fluid actuated rocl: drill coinprising a valve chest provided with a plurality of spaced supply ports and rcliet port means, a reciprocating valve in the chest tu control the supply ports and the s rc l port means and having `an end pi'ojecv from the valve chest, said valve being;` hollov.' and provided with a iertures extending through the side of the valve to communil cate with the said relieil port means in the valve chest, a lever` mounted pivotally on the valve chest to move said valve in one direction to close the supply ports and open the relief porting graduallyv whereby air in the air feed element may be gradually.' released, a spring in said valve Vlor aulomatically moving` the valve in the mainz-ite direction for closing the relief porting and opening the supply ports, and a spring in lha valve chest for holding the lever in a normally retracted position.

In testimony whereof l have signed this specification. 

